Klebsiella pneumoniae can naturally synthesize pyrroloquinoline quinone (PQQ), but current low yield restricts its commercialization. Here, we reported that PQQ production can be improved by simultaneously intensifying PQQ gene expression and glucose metabolism. Firstly, tandem repetitive tac promoters were constructed to overexpress PQQ synthesis genes. Results showed that when three repeats of tac promoter were recruited to overexpress PQQ synthesis genes, the recombinant strain generated 1.5-fold PQQ relative to the strain recruiting only one tac promoter. Quantitative real-time PCR (qRT-PCR) revealed the increased transcription levels of PQQ synthesis genes. Next, fermentation parameters were optimized to augment the glucose direct oxidation pathway (GDOP) mediated by PQQ-dependent glucose dehydrogenase (PQQ-GDH). Results demonstrated that the cultivation conditions of sufficient glucose (??32&nbsp;g/L), low pH (5.8), and limited potassium (0.7&nbsp;nmol/L) significantly promoted the biosynthesis of gluconic acid, 2-ketogluconic acid, and PQQ. In optimum shake flask fermentation conditions, the K. pneumoniae strain overexpressing PQQ synthesis genes under three repeats of tac promoter generated 363.3&nbsp;nmol/L of PQQ, which was 2.6-fold of that in original culture conditions. In bioreactor cultivation, this strain produced 2371.7&nbsp;nmol/L of PQQ. To our knowledge, this is the highest PQQ titer reported so far using K. pneumoniae as a host strain. Overall, simultaneous intensification of pqq gene expression and glucose metabolism is effective to improve PQQ production.When asked to identify the position of a sound, listeners can report its perceived location as well as their subjective certainty about this spatial judgement. Yet, research to date focused primarily on measures of perceived location (e.g., accuracy and precision of pointing responses), neglecting instead the phenomenological experience of subjective spatial certainty. The present study aimed to investigate (1) changes in subjective certainty about sound position induced by listening with one ear plugged (simulated monaural listening), compared to typical binaural listening and (2) the relation between subjective certainty about sound position and localisation accuracy. In two experiments (N?=?20 each), participants localised single sounds delivered from one of 60 speakers hidden from view in front space. In each trial, they also provided a subjective rating of their spatial certainty about sound position. No feedback on response was provided. Overall, participants were mostly accurate and certain about sound position in binaural listening, whereas their accuracy and subjective certainty decreased in monaural listening. Interestingly, accuracy and certainty dissociated within single trials during monaural listening in some trials participants were certain but incorrect, in others they were uncertain but correct. Furthermore, unlike accuracy, subjective certainty rapidly increased as a function of time during the monaural listening block. Finally, subjective certainty changed as a function of perceived location of the sound source. These novel findings reveal that listeners quickly update their subjective confidence on sound position, when they experience an altered listening condition, even in the absence of feedback. Furthermore, they document a dissociation between accuracy and subjective certainty when mapping auditory input to space.While urban forests are often identified as part of climate change adaptation and mitigation strategies, less attention has been given to vulnerabilities urban trees may have to a changing climate and practitioners' response to those vulnerabilities. Yet, current planting and management decisions will impact how urban forests fare under future climatic conditions. We explore a case study of Mississauga (Ontario, Canada) to examine (1) if common urban forest species are vulnerable to two scenarios of projected climate change, (2) the experiences and responses of urban forestry practitioners to climate change, and (3) whether urban forestry practitioners' experience and practice are aligned with the vulnerability assessment. Vulnerabilities of 27 common species were examined based on 2071-2100 regional climate projections. https://www.selleckchem.com/products/bgb-16673.html Interviews were then conducted with practitioners working in the public and private sectors. The results suggest that the majority of examined species will be vulnerable to multiple conditions associated with projected climate. Practitioners all perceive recent changes in climate and extreme weather patterns, but do not prioritize future climate conditions in their species selection decisions. Moreover, they expressed uncertainty about how to make species selection decisions in light of climate change. Given the predicted vulnerabilities, alternative species need to be considered or more management resources (e.g., for watering) will be required to maintain the current composition. However, the lack of focus on future conditions by practitioners raises concerns, while also highlighting the need for more information about appropriate management strategies.Microplastic (MP) contamination in marine organisms is a growing field of research internationally. However not much is known about MP presence in invertebrates in southern Africa. The aim of this study was to determine whether MPs occurs in mussels prevalent in Cape Town, South Africa. Mussels (Mytilus galloprovincialis, Choromytilus meridionalis and Aulacomya ater) were sampled at 27 sites in October 2018 and MPs were recorded in 98% of mussels analysed. Most MPs were filaments, dark in colour and the size ranged between 50 and 1000&nbsp;?m. There were no significant differences in MPs between the mussel species, with an average of 2.33 (standard error?±?0.2) MP particles/g and 4.27 (standard error?±?0.5) particles/individual being recorded for all sites combined. This is the first record of MPs in mussels in the region and provides a baseline for further investigations and monitoring of MPs.The authors signal an error in Fig.&nbsp;1b which does not show the correct set of plants and should be replaced with the included new figure.